Kristen Bell and Dax Shepard know how to keep things spicy in the bedroom, but it involves actions outside of their home.

E! News caught up with the couple at the CHiPs premiere in Los Angeles Monday where they both sounded off on how they keep the heat burning in their marriage. "She only thinks I'm sexy when I over-tip people," Shepard revealed. "That seems to be the thing that makes her horniest, so I do that frequently."

By frequently, Shepard might have meant seldom. "I'm older so I only get aroused about once every six months," Shepard joked. "It's just physiology, so when that happens, that bi-annual arousal, I tip like a mother."

Bell echoed Shepard's sentiments and added that his seat "in the director chair" also gets her in the mood.

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"When he's kind I tell him it's the sexiest you can be," she said. "If he's looking to woo me he just needs to let me see him tip someone royally and handsomely."

Of course, a little costume change never hurt anyone. Bell thought her risqué red bathing suit from their comedy would kick things up a notch in their marriage, but the Veronica Mars star admitted her husband was "nonplussed."

"He said my chest was pulling focus," Bell quipped, adding that it "flattered" her "for some reason."

To make her breasts look extra large in the smokin' bathing suit, Bell stopped breastfeeding for a day.

"I'm not well-endowed and I was breastfeeding at the time and I thought, this is my chance to really go that extra physical mile for my craft, you know? Like Christian Bale and Robert De Niro have done," Bell joked. "I'll stop breastfeeding for a day...'Kids, if you're hungry, go to the fridge. The food truck is not open today.'"